Hydroceles are not usually dangerous and do not require treatment unless they decrease the blood supply to the penis or cause pain or embarrassment, according to WebMD. If hydroceles return, get larger or cause discomfort, a medical professional may need to perform a surgical procedure.
Hydroceles tend to go away on their own, but they do not usually go away on men over the age of 65, states WebMD. A physician may use a needle to drain fluid from hydroceles, but they often still return after this procedure. This procedure is usually only used on men who cannot get surgery because of infection or recurrence risks.
It is not known what causes most hydroceles, as of 2015, notes WebMD. Some newborns may have hydroceles because of an opening located between the abdomen and scrotum that did not close properly. Surgery or an injury to the groin or scrotum area may cause hydroceles later in life. Hydroceles may also be caused by an inflammation or infection in the testicles or epididymis. In rare cases, hydroceles may be caused by cancer in a testicle or the left kidney.
Hydroceles do not always cause symptoms, according to WebMD. Some symptoms that may be associated with hydroceles include a feeling of pressure at the base of the penis; an enlarged scrotum; or redness, pain or swelling of the scrotum.